PURPOSE: To ensure a distance necessary for taking-off and landing even if the site area of an airfield is small.

CONSTITUTION: A main runway 1 is formed of an annular-like circle or ellipse. A taking-off and landing straight line port 2 projecting out of the main runway 1 is provided in at least one circumferential section of the main runway 1. The annular main runway 1 is provided with a bank for preventing an airplane from running out by centrifugal force. A terminal building 4 is built inside the main runway 1. A road 5 leading to the terminal building 4 or the like is provided under ground of the main runway 1. This circuit type runway is constructed to be an artificial floating island as a whole so that it can be turned to correspond to the wind direction and only two landing and taking-off straight line ports 2 can deal with a number of airplanes 3. Also, the annular main runway 1 may be fixed and only the taking-off and leading straight line parts 2 may be movable to cope with the wind direction.